When you have collected the indicated amount of pages which are scattered around Manhattan you will be able to read the corresponding full issue of Spider-Man comic.

1st Black Cat:
Collect 125 Pages

1st Gwen Stacy:
Collect 350 Pages

1st Iguana:
Collect 250 Pages

1st Lizard:
Collect 15 Pages

1st Rhino:
Collect 50 Pages

1st Scorpion:
Collect 80 Pages

1st Smythe:
Collect 500 Pages

1st Spider-Man:
Collect 5 Pages

Modern Lizard:
Collect 30 Pages

Vs. Vermin:
Collect 175 Pages